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fissile Syllabification: fis·sile
Pronunciation: /ˈfisəl/ /ˈfiˌsīl/

Definition of fissile in English:


1(Of an atom or element) able to undergo nuclear fission: a fissile isotope
More example sentences
  • It resumed the production, and testing of uranium enrichment centrifuges that can make fissile material for nuclear reactors or weapons.
  • It also is the toxic and radioactive byproduct of enriched uranium, the fissile material in nuclear weapons.
  • As a general rule, however, the biggest hurdle for a would-be nuclear power is the acquisition of fissile material - enriched uranium or plutonium.
1.1(Chiefly of rock) easily split: flat-bedded and very highly fissile shale
More example sentences
  • For example, fissile slates tend to yield much flatter particles than massive granites.
  • This horizon, up to 1.3 m thick, is a black, highly fissile shale.
  • The fossiliferous horizons occur in greenish to greyish siltstones and brown to black fissile shales associated with mollusc shells.


Mid 17th century (in the sense 'easily split'): from Latin fissilis, from fiss- 'split, cracked', from the verb findere.



Pronunciation: /fiˈsilədē/
Example sentences
  • During compaction of siliciclastic muds the flaky clay particles are realigned to be parallel to each other and impart a fissility (a direction of easy splitting) to the rock, which is commonly called shale.

Words that rhyme with fissile


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Word of the day fortissimo
Pronunciation: fɔːˈtɪsɪməʊ
(especially as a direction) very loud or loudly